Anything to make me crazy.

[rick kirby]

Have a 2017 Challenger YT. It always seems to be something with this thing, now it's the ACs turn.
Decided to go test them out for an upcoming trip down south.
Started the generator and tried to start the front unit, no go. Nothing.
Turned on the rear, started up. Went back to the front and tried it again. It started. Wth ?
Went back and shut the rear one down and let the front run a while. Shut it off and tried a couple minutes later.
Tried the back, no go.
Went back and tried the front, started. Shut it off and tried to restart. Nope.
I'm too old for this crap. This coach has less than 2500 miles on it and I can't trust it to go to the corner.
Called the dealer, waiting for a return call.
I don't mess up often, but this is one investment that's going to kill me.

[JamieGeek]

A lot of the A/C's have a delay built in. I know ours does: Especially if I've already run it or its been running a while.

I'll turn it on and then check again in a few minutes if it didn't come on right away.

[rick kirby]

Never had anything like a delay on a startup. What would be the point of it ?

[rick kirby]

And how does that work should you need it down the road?? How long is your delay ?

[JamieGeek]

I believe the delay is built in the thermostat to protect the compressor.

Running down the road I'll leave the thermostat set to a very low temp on A/C and turn the genny on or off to control when I need the roof A/C. When using it this way I hardly notice the A/C delay as there is also the delay from the genny turning on (it will wait until the RPM's stabilize before turning on 120V).

On ours the delay is something like 2 or 3 minutes max.

[rick kirby]

Wow, ok, I'll try it and see what happens.

[rick kirby]

Looks like it is a delay. I think I will check into having the thermostat replaced and installing a hard start capacitor. Thank you.

[Mo_Mike]

Originally Posted by JamieGeek

I believe the delay is built in the thermostat to protect the compressor.

Running down the road I'll leave the thermostat set to a very low temp on A/C and turn the genny on or off to control when I need the roof A/C. When using it this way I hardly notice the A/C delay as there is also the delay from the genny turning on (it will wait until the RPM's stabilize before turning on 120V).

On ours the delay is something like 2 or 3 minutes max.

Ours has the delay also. I didn't think much about it since our house units do the same thing to protect the compressor and keep it from trying to send against high head pressure.

[Laco]

That delay protects the AC compressor. It should be set to about five minutes. If the compressor has been running and shuts down, the head pressure in the compressor from the Freon, cold on one side, hot on the other, will be too much for the compressor motor to overcome if it try's to start. (Could blow the compressor) That five minute delay allows the pressure to equalize on both sides.

[Chance]

Originally Posted by rick kirby

Never had anything like a delay on a startup. What would be the point of it ?

Electric motors are often protected from trying to restart while still hot because of the required higher starting current. A time delay helps lower temperature.

The higher A/C head pressure the compressor would need to start against (mentioned above) also doesn't help. It would pull higher start-up current even longer, adding to heat buildup.

Most things that add cost and complexity are usually required. Engineers are not likely to add a time delay just for the fun of it.

[rick kirby]

But why a delay at the initial startup ? Nothing is hot, in fact, never used since new in February.

[Laco]

The AC does not need the delay on initial startup, that is just a function of the thermostat. Most thermostats in RV's have the delay on initial as well as restart. Home thermostats generally do not delay on initial startup, only on a restart. My guess, it cost less to make a thermostat that always delays starting, rather then making it intelligent enough to know if its an initial start or a restart. Its all about dollars.

[rick kirby]

Thank you. So it must be when someone swaps out the thermostat for a digital, the delay would be gone ?

[Laco]

Not necessarily, both my last coach and current Gemini have digital thermostats both of which introduce the delay both on initial startup and restart. I frankly don't find it objectionable enough to do anything about it.

[rick kirby]

What's objectable is why I can't wrap my stupid brain around it. Lol